People gather at the scene of a car bomb attack in central Baghdad, Iraq, Wednesday, Nov. 14, 2012. Iraqi insurgents unleashed a new wave of bombings across the country early Wednesday targeting security forces and civilians, killing and wounding scores of people, police said. (AP Photo/Khalid Mohammed)

Photo: Khalid Mohammed, Associated Press

People gather at the scene of a car bomb attack in central Baghdad,...

From a busy market to a university campus, a series of bomb attacks swept through Iraq on Wednesday, killing at least 20 people and wounding more than 100, the Iraqi police and security forces said.

The attacks struck civilian, government and security targets. There was no immediate claim of responsibility for any of the blasts, which were spread out in more than half a dozen provinces in Iraq.

The extent to which any of the attacks were coordinated was not clear, but they were some of the most widespread in recent weeks.

Violence in Iraq is less frequent than at the height of the insurgency, although militias have often struck at the country's security forces, sometimes with many casualties, to undermine confidence in the government's ability to keep order.

On Wednesday, some of the worst violence was in the north. In the city of Kirkuk, nine people were killed and 31 wounded by three car bombs targeting headquarters of Kurdish and Turkmen political parties. At the southern entrance to the province, the governor, Omar al-Humairi, escaped an assassination attempt in which a roadside bomb targeted his convoy, and a car bomb blew up inside a parking lot in the west of the city, wounding one person.

In Mosul, another city in the north, a bomb exploded as an Iraqi army patrol passed, wounding five service members and two civilians. In Diyala province, 13 civilians were wounded in three separate attacks.